The present investigation attempted to determine particular vocationally-related behaviors common to second semester seniors in two inner-city high schools, to gather data about these behaviors, to analyze and evaluate these data, and to draw conclusions about the relative vocational maturity of individuals in the study population. Data were gathered in six vocational maturity component areas. School achievement, as measured by grade point averages at two grade levels, emerged as the best predictor of a rating of vocational maturity. More promising for future vocational maturity researchers is the finding that the vocational planning and job knowledge sections of the research instrument emerged as vocational maturity rating predictors almost as powerful as school achievement. This finding provides a basis for direction in the development of other vocational maturity rating instruments. The finding indicates that an assessment of students' vocational-educational plans or lack thereof, and steps taken toward plan implementation, together with an assessment of general job knowledge, would provide a vocational guidance worker with a relatively valid rating of an individual's vocational maturity. (AUTHOR)